# 练习 9.9：电池升级 在本节最后⼀个 electric_car.py 版本中，给
# Battery 类添加⼀个名为 upgrade_battery() 的⽅法。这个⽅法
# 检查电池容量，如果电池容量不是 65，就设置为 65。创建⼀辆电池容
# 量为默认值的电动汽⻋，调⽤⽅法 get_range()，然后对电池进⾏升
# 级，并再次调⽤ get_range()。你将看到这辆汽⻋的续航⾥程增加
# 了


class Car:
    """⼀次模拟汽⻋的简单尝试"""

    def __init__(self, make, model, year):
        """初始化描述汽⻋的属性"""
        self.make = make
        self.model = model
        self.year = year
        self.odometer_reading = 0

    def get_descriptive_name(self):
        """返回格式规范的描述性名称"""
        long_name = f"{self.year} {self.make} {self.model}"
        return long_name.title()

    def read_odometer(self):
        """打印⼀个句⼦，指出汽⻋的⾏驶⾥程"""
        print(f"This car has {self.odometer_reading} miles on it.")

    def update_odometer(self, mileage):
        """将⾥程表读数设置为给定的值"""
        if mileage >= self.odometer_reading:
            self.odometer_reading = mileage
        else:
            print("You can't roll back an odometer!")

    def increment_odometer(self, miles):
        """让⾥程表读数增加给定的量"""
        self.odometer_reading += miles


class Battery:

    def __init__(self, battery_size=40):
        """初始化电池的属性"""
        self.battery_size = battery_size

    def describe_battery(self):
        """打印⼀条描述电池容量的消息"""
        print(f"This car has a {self.battery_size}-kWh battery.")

    def upgrade_battery(self):
        if self.battery_size != 65:
            self.battery_size = 65

    def get_range(self):
        """打印⼀条消息，指出电池的续航⾥程"""
        if self.battery_size == 40:
            range = 150
        elif self.battery_size == 65:
            range = 225
        print(f"This car can go about {range} miles on a full charge.")


class ElectricCar(Car):
    """电动汽⻋的独特之处"""

    def __init__(self, make, model, year):
        """先初始化⽗类的属性，再初始化电动汽⻋特有的属性"""
        super().__init__(make, model, year)
        self.battery = Battery()


eCar = ElectricCar("nissan", "leaf", 2023)
eCar.battery.get_range()
eCar.battery.upgrade_battery()
eCar.battery.get_range()
